Dissecting the nanohertz gravitational wave sky: Frequency-correlated anisotropy induced by eccentric supermassive black hole binaries
The study tests if frequency-correlated anisotropy in gravitational wave signals from Pulsar Timing Arrays can detect eccentricity in supermassive black hole binaries (SMBHBs). By comparing sky maps at different frequencies, researchers found that eccentric binaries produce correlated power distributions, providing a 'smoking gun' to distinguish them from circular ones. This method is viable and sensitive enough to detect eccentricity at 3-sigma in over half of cases.